Borrowings and Credit Arrangements - Company's Borrowings (Detail) - USD ($) $ in Millions	Dec. 28, 2019	Sep. 28, 2019
Debt Instrument [Line Items]
Current portion of long-term debt	$ 302.2	$ 271.4
Total long-term debt obligations	2,769.4	2,783.6
Total debt obligations	3,071.6	3,055.0
Term Loan
Debt Instrument [Line Items]
Current portion of long-term debt	46.8	37.4
Long term debt obligations. excluding convertible notes	1,434.3	1,452.4
Securitization Program
Debt Instrument [Line Items]
Current portion of long-term debt	250.0	234.0
2025 Senior Notes
Debt Instrument [Line Items]
Long term debt obligations. excluding convertible notes	937.8	937.3
2028 Senior Notes
Debt Instrument [Line Items]
Long term debt obligations. excluding convertible notes	394.1	393.9
SSI [Member]
Debt Instrument [Line Items]
Current portion of long-term debt	5.4	0.0
Long term debt obligations. excluding convertible notes	$ 3.2	$ 0.0

Long term debt obligations without convertible notes.

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